code: def checkpoint(self):
      return self.state
  
file_path: ray/doc/source/ray-core/doc_code/actor_checkpointing.py
imports: import os
  import sys
  import ray
  import json
  import tempfile
  import shutil
label_desc: Use image node_id 3 for calling the Worker obj's underlying member method code with example usage: obj.checkpoint() and returns: self